Mutual relationship between Tau and central insulin signalling: consequences for AD and Tauopathies ?

Alzheimer ’s disease (AD) is a progressive neurodegenerative disorder mainly characterized by cognitive deficits and neuropathological changes such as Tau lesions and amyloid plaques, but also associated with non-cognitive symptomatology. Metabolic and neuroendocrine abnormalities, such as alterations in bo dy weight, brain insulin impairments and lower brain glucose metabolism, that often precede clinical diagnosis, have been extensively reported in AD patients. However, the origin of these symptoms and their relation to pathology and cognitive impairments remain misunderstood. Insulin is a hormone in volved in the control of energy homeostasis both peripherally and centrally, and insulin resistant state has been linked to increased risk of dementia. It is now well established that insulin resistance can exacerbate Tau lesions, mainly by disrupting the balance between Tau kinases and phosphatases . On the other hand, emerging literature indicates that Tau protein can also modulate insulin signalling in the brain, thus creating a detrimental vicious circle. The following review will highlight our current understanding on the role of insulin in the brain and its relation to Tau protein in the context of AD and Tauopathies. Considering that insulin signaling is prone to be pharmacologically targeted at multiple levels, it constitutes an appealing approach to improve both insulin brain sensitivity and mitigate brain pathology with expected positive outcome in term of cognition...
Source: Neuroendocrinology - Category: Endocrinology Source Type: research